Chamfer resection guides are used in orthopedic surgery for resecting the distal end of the femur. Currently available chamfer resection guides are monolithic instruments and are secured to a distal femoral resection by means of either pins or orthogonal flange protruding from the distal face of the instrument. Once the instrument is coupled to the distal femur and its position is established, adjustment of the instrument requires that the chamfer resection guide is removed and its reference features are repositioned by some other means. These features typically are either holes in the distal femur, or a rough anterior resection.
Other devices used to refine the final position of he chamfer resection guide and subsequently the implant are used in steps either prior to choosing the best size chamfer resection guide (a step known as sizing the femur) using a femoral caliper or by removing the chamfer resection guide altogether and using another device to relocate the referencing features that the chamfer guide was attached to.
A chamfer resection guide is the best instrument for checking the final position of the resections before making the resections. This is because the resections are made through the guide, so a reference plane (i.e. a bladerunner) can be placed through the guide to re-check the resection levels. Instruments that attempt to refine the final position of the chamfer guide without the guide in place does not provide the user an accurate means of verifying the resection levels of the final implant. Additionally, if the chamfer resection guide does need to be repositioned, removal of the guide and adjustments of its referencing features takes additional time and induces a chance for additional error.